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Seawater desalination is useful for supplementing the freshwater supply to coastal industrial parks. However, high cost and energy consumption is a serious disadvantage of typical desalination plants. Subsidy from government can incentivize investments to increase supply of desalinated water. However, the subsidy must be calibrated to minimize cost to the public. A graphical pinch analysis method is developed to determine the optimal subsidy for water desalination, taking into account local water price as well as supply and demand. This method uses the Limiting Composite Curve (LCC) as basis for the optimal subsidy; the minimum quantity of desalinated water is also determined. Next, the minimum subsidy is determined by relaxing the subsidized price of desalinated water. The proposed method is demonstrated through an illustrative industrial park case study. Results show that the optimal subsidy for desalinated water is $0.35/t. Sensitivity analysis shows that, when subsidy increases, demand for desalinated water increases and displaces the demand for other water resources. Furthermore, analysis of the Water-Energy Nexus is conducted to find the minimum energy consumption per unit of water at the optimal subsidy level. The proposed method can provide options for the industrial park to achieve the economic development, while minimizing the environmental impact of water supply mix. Image 1 • A graphical method is developed to optimize the subsidy of desalinated water. • The method is applied to a case study on Qingdao. • The water-energy nexus aspects of the problem are also discussed. • Sensitivity analysis with respect to subsidy level is performed. • Practical implications for water resource management are discussed. [ABSTRACT FROM AUTHOR]

Abstract Household energy consumption and carbon footprints change with household characteristics such as type of residence, energy system performance, vehicle performance, and users' behavioral patterns. Accordingly, alternative energy technologies, such as clean electricity, hydrogen fuel cells, and energy efficient interventions, are being adopted in many parts of the world to reduce the residential, industrial, and transportation emissions. This paper presents a comprehensive research framework to identify the most desirable building retrofits and incentive schemes for Canadian households. Globally available incentive policies for low-emission vehicles and locally available retrofit options for single-family detached houses were identified during this study. A decision support tool based on life cycle thinking was developed to assess economic parameters, such as capital investment and annualized consumer cost, and environmental parameters such as greenhouse gas emissions. In order to rank and select the most desirable building retrofit, the TOPSIS ranking method was used. The linear programing graphical method was used to select the best incentive policy for low-emission vehicles. Finally, scenario analysis was used to compare different households based on regional economic and environmental characteristics. Provinces which have low-emission electricity grids such as Manitoba, British Columbia, and Quebec can primarily focus on incentives for electrified transportation. Additionally, the incentives for retrofits such as greener appliances and heating, ventilation, and air conditioning systems would also significantly reduce building carbon footprint. Conventional residential buildings with fossil fuel vehicles are more desirable for provinces like Saskatchewan, Alberta, and Nova Scotia which have high-emission electricity grids. Based on the outcomes of this research, a scientific incentive planning and management approach considering regional economic and environmental characteristics was introduced. Highlights • Life cycle thinking-based economic factors and operating emissions of single-detached household were analyzed. • Possible retrofit incentives and retrofit combinations were ranked based on regional economic and environmental factors. • Regions with low emission electric grids can primarily focus on incentives for electrified transportation system. • Conventional households and fossil-vehicles are desired for the areas with higher emission factor electric grid. [ABSTRACT FROM AUTHOR]

Global warming may cause the average atmospheric temperature to exceed 2 °C by the end of this century, instigating climate change and adversely affecting human lives. Emissions of carbon dioxide (CO 2) should be reduced to overcome the problems of global warming and climate change. The applications of negative emission technologies (NETs) are proposed to reduce terrestrial CO 2 and are identified as one of the prominent options for the energy system transition. Most negative emission technologies require energy to function, which has to be produced from additional energy sources. Understanding the interdependence of the energy sources and NETs for planning the carbon-constrained energy sector is essential. A novel graphical approach, founded on the concepts of Pinch Analysis, to decarbonize the energy sector is purported in this paper. The proposed method determines the minimum integration of negative emission technologies required to attain the allowed CO 2 emission limit while satisfying the energy demand. Four different examples are used to show the applicability of the suggested approach with different NETs: carbon capture and sequestration (CCS), bioenergy with carbon capture and storage (BECCS), and direct air capture (DAC). In these examples, renewable-based energy sources, fossil-based energy sources, as well as energy-producing negative emission technologies are used as compensatory energy sources. The proposed graphical approach has the potential to be used as a planning tool to decarbonize the energy sector involving interdependent energy sources and NETs. [Display omitted] • Negative emission technologies help decarbonize the energy sector. • Identified dependence between the energy sector and negative emission technologies. • A graphical method is proposed to integrate negative emissions technologies. • Determined minimum compensatory energy for adopting negative emission technologies. • The proposed graphical approach provides insight into the overall systems planning. [ABSTRACT FROM AUTHOR]

The overall top-layer design for chemical production, carbon emission and production cost is significant for the sustainable development of chemical industry. Industrial structure adjustment and low-carbon technology retrofit are generally served as the alternatives for policymakers and plants to simultaneously meet the energy demand and carbon emission limit. To further extend the practical application of Carbon Emission Pinch Analysis (CEPA) for low-carbon methanol production planning on the supply side, this paper presents four scenarios for the methanol industry in 2020 in China. A graphical method of Chemical Production Pinch Analysis (CPPA) combining with the first-order and single-variable grey model (GM(1,1)) is conducted to analyze the interaction between energy demand and carbon emission. A two-step tabular method is also proposed to search the optimal planning for achieving the minimum production cost and CO 2 emission. The results show that the coal-to-methanol route would continually dominate the major share of methanol supply and CO 2 emission in the overall methanol industry due to the energy structure of China. Options of developing biomass-methanol technology, shifting the production share from coal to low-carbon routes and retrofitting with CO 2 capture and storage (CCS) in coal-methanol plants could be considered to simultaneously achieve the targets of energy supply, carbon emission constraint and minimum production cost. [ABSTRACT FROM AUTHOR]

The palm oil industry has had to undergo rapid development in order to cope with the increasing demand from consumers year by year. The palm oil industry is receiving criticism from various parties on the issue of sustainability. This paper presents the development of a Palm Oil Mill Sustainability Index that enables millers to assess the sustainability performance of palm oil mills against benchmarks, and to differentiate between the performance of each mill. The assessment was performed via the adoption of a Proximity-to-Target approach that measures the current sustainability performance of the industry relative to policy targets. The industry's comparable performance was observed in terms of sustainability and indicators through a graphical method. The resulting Palm Oil Mill Sustainability Index scores were translated into a five-point rating system to describe the sustainability performance levels for different mills i.e. excellent, good, fair, poor, and very poor. Based on the Palm Oil Mill Sustainability Index scores and rating system, weak performance indicators were identified, for example, excessive use of water consumption due to inappropriate operation of hydrocyclones. By identifying the weak performance indicators, practical recommendations and measures for improvement can be proposed and the Palm Oil Mill Sustainability Index scores recalculated to evaluate the effectiveness of the proposed sustainability performance strategy. Selected palm oil mills in Malaysia were used as a case study to demonstrate the applicability of the framework. The results provide empirical evidence to support a decision-support-system for enhancing palm oil mill sustainability performance, so as to achieve a balance between environmental, economic, and social aspects in the palm oil mill sector. [ABSTRACT FROM AUTHOR]

A thermodynamically oriented method is developed to identify the theoretical and practical limits of pressure-retarded osmosis (PRO) on converting salinity gradient power to mechanical energy under constant operating pressure with infinite and finite mass exchange area, respectively. It is proved that pinch analysis can be used to find the mass exchange limit of PRO, and according to which draw and feed streams can be plotted on a graph of net osmotic pressure - water exchange. Based on the graphical method, an expression of optimal pressure change is derived that achieves the maximum work extraction of a PRO process with single draw/feed stream. Moreover, problem table method is presented that serves as an analytical procedure to determine the maximum extractable work of the conceptualized multi-stream PRO process. Examples of both a PRO process with a draw stream (0.6 M NaCl seawater) and a feed stream feed (0.015 M NaCl river water) and a multi-stream PRO are included to illustrate the proposed methods. Results of the former example show that the counter-current design achieves 30.85% and 31.49% increase, respectively, in the maximum theoretical and practical work output, compared with the co-current design. The latter example shows that the problem table method produces a 20.47% increase in the work output, compared with the standalone design. [Display omitted] • Visualized and easy-to-use methods to determine energy conversion limit of PRO •Applicable to one-draw-one-feed PRO and multi-stream PRO energy targeting problems •Counter-current design extracts 30%+ more energy for seawater-river water PRO •Finite area seawater-river water PRO is more efficient with feed/draw ratio <1 •Integrated design of multi-stream PRO achieves 20%+ increase of work output [ABSTRACT FROM AUTHOR]

Hydrogen and water are important resources for refineries. Pinch based conceptual method is an effective tool for fresh resource conservation of hydrogen and water networks. A novel graphical method is proposed to identify the minimum consumption of fresh resource and design the network for both hydrogen and water networks with single contaminant. This method replaces traditional total flow rate and absolute concentration constraints with hydrogen load and relative concentration, constructing the composite curves in contaminant load versus hydrogen load diagram to perform the targeting and design process. Furthermore, the proposed method can be reinforced by integrating purification reuse, conserving more fresh hydrogen and further reducing the waste discharge. This new method is visible, simple and easy to understand, suitable to both hydrogen and water networks. Three cases are studied to illustrate its application. [ABSTRACT FROM AUTHOR]

In this study, the effects of various blast furnace slag (BFS) contents on the performance of cement pastes and pavement were investigated at two levels, the micro and the macro. At the micro level, the strength and chemical properties of cement pastes containing various percentages of BFS and subjected to different water curing periods were evaluated. At the macro level, the structural and sustainability performance of airport concrete pavements were studied. In this regard, several structural design charts were developed to determine the thickness of the concrete slab required to withstand traffic loadings for various versions of aircraft design and subgrade strengths. The sustainability of the concrete pavements was assessed in terms of fuel requirements and greenhouse gas (GHG) emissions. In addition, a simple graphical method was proposed for comparing structural and environmental performance of concrete pavements with respect to BFS content, subgrade strength, different versions of the aircraft design, fuel requirements and GHG emissions for pavement construction. Based on the results obtained using the proposed method and the structural and sustainability analyses, scenarios are suggested for choosing preliminary BFS content. [ABSTRACT FROM AUTHOR]

Abstract: In the oil refining and petrochemical industry, hydrogen flows in so-called hydrogen networks are a common feature. A practical problem in hydrogen network analysis is to identify the minimum fresh hydrogen input flowrate to ensure that the hydrogen streams produced by combining the flows of internal sources satisfy certain concentration specifications of sinks for hydrogen and impurities such as H2S. To tackle this problem, this paper presents a novel graphical procedure, much inspired by the pioneering work of that makes use of the unique features of ternary composition diagram for three-component systems. In addition, accounting for constraints on flowrates inside a ternary visualization diagram is another novel aspect of this graphical method. Two literature case studies based on hydrogen systems with multiple impurities are solved to illustrate the effectiveness and elegance of the proposed method. [Copyright &y& Elsevier]

Abstract: Consumer-based ocean conservation efforts focus attention on seafood that is produced in an “eco-friendly” manner. However, many species can be produced either in aquaculture operations or harvested within wild capture fisheries, and each mode of production differs in their environmental impacts as well as their energy requirements. Complicating the assessment of eco-friendly seafood is the fact that seafood is a global commodity, the suppliers of which utilize a variety of methods to distribute the product from producer to consumer (e.g. ship, truck, airplane). Like the modes of production, these various modes of distribution differ in their energy intensity. This analysis assesses the overall energy requirements of production and distribution (E P&D) of seafood to evaluate how the energy costs of distribution influence the total energy cost of seafood produced by different methods. This paper develops the concept of energy isolines as a tool to assess E P&D. Isolines are a graphical method to succinctly integrate multiple distance assessments so that the best sourcing option can be determined. The isolines are then used to assess how the energy cost of distribution functions as a component of the overall energy cost, and how this influences the E P&D of a product originating from two different sources with inherently different energy costs of production. Using scallops and salmon as examples, this analysis has revealed that an “eco-friendly” seafood commodity (one produced with less energy) produced far from its destination market could have a higher total E P&D compared to a local, less “eco-friendly” product (that takes more energy to produce). Finally, this paper evaluates strategies to minimize the overall E P&D of seafood. Overall, further work on energy audits of seafood focused the need to maintain a global perspective to determine seafood with the lowest overall energy cost of production and distribution. [Copyright &y& Elsevier]

Polypropylene fiber, as a micro-scale reinforcement, can effectively inhabit the continuous micro-crack propagation of concrete during service. This paper aimed at examination of the fatigue life of polypropylene fiber reinforced concrete (PFRC) as subjected to repetitive compressive stress at multiple levels. A total of 18 groups of prismatic specimens were tested for different stress levels and polypropylene fiber parameters (volume fractions and aspect ratios). A two-parameter Weibull distribution was employed to describe the fatigue life probability distribution of PFRC. The shape parameter and characteristic life parameter were derived by averaging the values estimated by graphical method, moment method and maximum likelihood estimation method. The results indicated that the addition of polypropylene fiber into the concrete matrix can remarkably prolong the fatigue strength of concrete. Compared with plain concrete, the fatigue strength of PFRC could be increased by up to 28.1% under the failure probability of 5%. The fatigue life of PFRC was increased with an increase in the polypropylene fiber volume fraction up to 0.15%. However, the fatigue life of PFRC was decreasing with an increase in the fiber aspect ratio. The PFRC specimen with a volume fraction of 0.15% and an aspect ratio of 167 possessed the highest fatigue compressive strength among all the designed specimens. The fatigue life probability distribution of PFRC also obeyed the two-parameter Weibull distribution. Finally, a single-logarithm fatigue equation for PFRC was developed with both fiber parameters and failure probabilities taken into account, which can realistically predict the fatigue life of PFRC. This research outcome provides new knowledge and database that underpin the future development of design specifications for PFRC structures. • Cheap polypropylene fiber can help prolong the fatigue life of concrete. • Fatigue damage mechanism and fiber reinforced mechanism are revealed. • A unified fatigue equation is developed with consideration of failure probability. [ABSTRACT FROM AUTHOR]

Sustainable water management is key to achieving sustainable development goals. Increasing water consumption prompts industrial plants to implement water conservation projects (WCPs) and improve the utilization efficiency of water resources. In this paper, we develop an integrated graphical method for the implementation of water conservation projects by considering both water-saving targets and investment costs with or without government subsidies. First, cost-benefit analysis for different projects is carried out. The unit water saving cost diagram is employed to rank the priority of implementation of each project. Then, the project combination that meets the expected water-saving goal is determined via water-saving pinch analysis. Finally, the water conservation potential and cost-benefit of the optimal project combination are estimated using the marginal cost curve diagram. Two scenarios are considered for the proposed graphical approach: with and without government subsidies. A chlor-alkali/polyvinyl chloride complex is used as an illustrative case study. The results indicate the proposed method can be used to screen out the feasible projects under the constraints of water-saving target and financial fund. • An integrated framework is developed for selecting profitable water conservation projects and maximizing financial gains. • Water conservation projects are ranked based on unit water-saving costs. • The optimal water conservation portfolio was determined for different subsidy ratios. • Marginal cost curves indicated the water savings potential of projects. [ABSTRACT FROM AUTHOR]